Moistening mechanism



Marh 9 1943.

w. E. DENISON MOISTENING MECHANISM Filed Sept. 25, 1939 2 Sheets-Sheet l Filed Sept. 25, 1939 2 She ets-Shee't 2 Patented Mar. 9, 1943 MOISTENING ME CHAN ISM William E. Denison, Chicago, 111., assignor to Ditto, Incorporated, Chicago, 111., a corporation of West Virginia Application September 25, 1939, Serial No. 296,464

8 Claims.

This invention relates to moistening mechanisms of a type adapted for use in a liquid process duplicating machine, or the like, for applying a solvent or other liquid upon a roller which is brought into contact with a surface to be moistened so as to apply a thin film of the liquid to the surface. It is the object of the invention to provide a new and improved form and arrangement of parts by which improved results shall be obtained in the matter of applying a film of moisture evenly and smoothly to the face of a copy sheet or other surface to be moistened.

In the construction illustrated, means is provided for feeding a supply of solvent to a strip of rubber having a great number of very fine perforations therethrough perpendicular to the plane of the strip and for feeding the solvent from such strip of rubber to the face of a roller by pressing the strip against the roller with the perforations open to the face of the roller for applying the solvent in turn to the face of a copy sheet or other surface to be moistened. In a second arrangement illustrated, the solvent is fed by spraying directly upon the face of the roller and is spread and distributed evenly and smoothly in the form of a thin film by engagement with a wiper comprising a strip of perforated rubber as above specified. In each of the constructions as above referred to, the solvent-applying member comprising the strip of perforated rubber .is supported by a cushioning pad formed of sponge rubber, with the openings in the perforated rubber strip blocked off and closed from the pores of the cushioning pad so as to prevent the passage of liquid from one part to the other. In a third form, however, the openings in the perforated rubber strip open directly to the pores of the pad so that the pad forms an effective part of the means for applying the solvent to the face of the roller and distributing it evenly therealong.

It is one of the objects of the invention to im prove moistening mechanisms in sundry details hereinafter pointed out. The preferred means by which the several objects are attained are shown in the accompanying drawings, in which-- Fig. 1 is a vertical sectional view" shown diagrammatically through a portion of a duplicating machine embodying one of the preferred forms of the invention;

Fig. 2 is a front face view of some of the parts as shown in Fig. 1 but with the wiper pad assembly swung downwardly out of normal operative position, and with some of the parts shown in vertical section;

Fig. 3 is a view similar to Fig. l but showing a modified form of arrangement;

Fig. 4 is a face view of the strip of rubber constituting the wiper of the Fig. 1 construction;

Fig. 5 is an enlarged detail view on a greatly increased scale showing the upper left hand corner portion of the strip of Fig. 4;

Fig. 6 is a horizontal sectional view taken substantially at the line 6-6 of Fig. 5; and

Fig. '7 is a vertical sectional view through a modified form of cushioning pad and perforated rubber strip assembly for substitution in the holder of either the Fig. 1 construction or the Fig. 3 construction.

Referring now to Figs. 1 and 2 of the drawings, 25 indicates the drum of a liquid process duplicating machine of any suitable type. Below the drum 25, there is an impression roller 26 rotatably mounted in position by means of a shaft 21 as is usual in machines of this type. At a short distance in rear of the platen or impression roller 25 (at the left in Fig. 1), two rollers 28 and 29 are rotatably mounted in cooperative relation to each other for feeding a copy sheet toward the right in said Fig. 1 into engagement between the drum 25 and the platen 26 The roller 23 is of course to be driven at sub stantially the same surface speed as that at which the drum 25 is driven, such parts being driven by any suitable means not shown. In rear of the feed rollers 28 and 29, a table 39 is provided, having side guide plates 34 and a top guide plate 32 thereon for directing sheets of paper to the bite of the feed rollers 28 and 29.

The means as shown in Figs. 1 and 2 for ap plying a quantity of solvent upon the face of the roller 28 comprises a bar 33 of sponge rubber provided with a strip 34 of sheet rubber or other rubber-like material provided with a great num ber of minute perforations 34a therethrough in parallel relation substantially perpendicular to the plane of the sheet and arranged in close proximity to each other in regular sequence throughout. In the arrangement shown in Figs. 1 and 2, the perforated strip 34 is secured to the pad or cushion 33 by a layer of rubber cement coextensive with the strip, the layer of cement serving to close and block off the openings 34a at the inner face of the strip so as to prevent their communication with the pores of the bar or pad 33. Solvent is applied to the face of the roller 28 by means of a pipe 35 fixedly mounted in position and having a series of openings 36 through its wall, only one of such openings being shown in Fig. 1. In the arrangement shown, the solvent is delivered to the pipe 35 by means of a second pipe 3'! positioned inside of the pipe 35, the pipe 3! being connected by a suitable tube 33 with any suitable source of solvent under pressure. As is shown in Figs. 1 and 2, the pipe 3'! is provided with openings 39 in its wall for the escape of the solvent from said pipe 31 into the interior of the pipe 35. In the arrangement shown, the openings 35 are so positioned as to cause the solvent to be sprayed from the pipe 35 directly on the face of the roller 23.

The means for supporting the moistening pad unit comprising the bar 33 and the strip 34 includes a supporting member 45 in the form of a channel made of sheet metal bent into form. This supporting means is substantially in accordance with the showing of a prior application in the name of Morrison, Serial No. 285,492, and forms no part of this present invention. The construction and operation of the supporting means will accordingly be described very briefly.

In the arrangement shown, the channel member 45 is provided at opposite ends with downwardly extending arm portions 4! which are pivotally connected at their lower ends with plates 42 which in turn are pivotally mounted upon bolts or pins 43 extending inwardly from the adjacent frame bars 44 of the machine, each of such plates 42 being provided with an outwardly extending lug 45 at its front edge portion. Below the pins 53, brackets 45 are provided for pivotally sup porting arms 4! which are provided with inwardly extending plate portions 48 which engage the front faces of the lugs 45. Pins or bolts 59 are pivotally mounted upon the brackets 55 and extend rearwardly through openings in the plates 58, having coiled springs 55 mounted on their rear end portions between the plates 48 and thumb nuts 51 secured by means of screw-threads on said pins 49. The arrangement is such that when the nuts are adjusted longitudinally of the pins 43, the pressure of the spring 50 upon the arms 4? and the plates 38 is varied for applying a contro-lled'pressure upon the lugs 45 and the plates 52. The arrangement is such that with the parts in the position as shown in Fig. 1 the springs 55 apply a forward pressure upon the lower edge portion of the bar 33 for pressing the wiper strip 34 with an adjustable degree of pressure against the roller 28 with the perforations 34a open to the roller.

Latch means 52 are pivotally' mounted upon the plates 42 in any suitable manner adapted by engagement with pins 53 carried by the supporting member All for holding such supporting member inlelevated position as shown in Fig. 1. When access is desired'to the bar or cushion 33 and the wiper member 34 for adjusting or replacing them, the latches 52 may be released from the pins 53 whereupon the supporting member 40 is adapted to swing rearwardly and downwardly into the positicn as shown in Fig. 2, the table 30 and its connected parts being first removed from the machine.

In the construction illustrated, the plates 42 are connected together by a cross plate bar 5 3 for holding the parts rigidly in position with respect to each other and for providing a stop for limiting the upward and downward swinging movement of th support 40 and the bar 53 carrying the wiper member 35., A shield 55 is also provided between the spray mechanism and the drum 25 for preventing splashing of the solvent upon the drum.

The arrangement is such that the pad 33 and attached strip 34 can be very quickly and easily reversed in the supporting member MI so as to bring either edge portion of the strip as desired into position to engage the roller 28.

The arrangement shown in Fig. 3 is similar to that shown in Figs. 1 and 2 except that the openings 56 through which the solvent is sprayed from the pipe 35 are located so as to direct the solvent toward the face of the perforated rubber strip 34 rather than directly toward the roller 28. The strip 34 accordingly in this arrangement acts both as an applying means for the solvent and also as a wiper, serving in this double capacity to cause the solvent to be spread very evenly and smoothly on the face of the roller.

In Fig. '7, a modified form of moistening pad unit is shown in which a strip 57 of perforated rubber similar to the strip 54 is secured in a.

modified manner to a sponge rubber pad or cushion 58 similar to the pad 33. In this modified form of unit, the strip 51 is secured to the pad by means of rubber cement, but the attachment by the cement is limited to the upper and lower edge portions only, as indicated at 59 and 60, so as to permit the openings through the strip to communicate with the pores of the sponge rubber pad throughout the major portion of their contact area. As a result of this arrangement, the pad 58 quickly absorbs a quantity of the solvent so as to serve as a reservoir as well as a wiper. It has been found in practice that both arrangements work very satisfactorily for causing the film of solvent to be smooth and even as applied to the roller 28.

While the forms of structure as illustrated in the drawings and a above described are preferred, the invention is not to be limited to the arrangements shown except so far as the claims may be so limited, it being understood that changes might well be made in the form and arrangement of parts without departing from the spirit of the invention.

I claim:

1. In a moistening mechanism, the combination of a roller, means for rotating said roller, and means for applying a quantity of liquid to said roller and distributing such liquid in the form of a thin film on the face of the roller, comprising a member in the form of a sheet of rubber-like material having a great number of minute perforations therethrough, and means for holding said member in engagement with the roller with the perforations open to the face of the roller for distributing the liquid along the face of the roller as the roller rotates.

2. In a moistening mechanism, the combination of a roller, means for rotating said roller, and means for applying a quantity of liquid to said roller and distributing such liquid in the a form of a thin film on the face of the roller,

comprising a member in the form of a sheet of rubber-like material having a great number of minute perforations extending through the sheet in parallel relation and arranged in close proximity to each other in regular sequence, and means for pressing said member into engagement with the roller with the perforations open to the face of. the roller for distributing the liquid along the face of the roller as the roller rotates.

3. In a moistening mechanism, the combination of a roller, means for rotating said roller, a strip of rubber-lik material having a great number of minute perforations therethrough substantially perpendicular to the plane of the strip, means for pressing said strip of rubber-like ma-= terial into engagement with the face of the roller with the perforations open to the roller, and means for spraying liquid on the face of said strip above said roller for application in the form of a thin film on the face of the roller.

4. In a moistening mechanism, the combination of a roller, means for rotating said roller, and means for applying a quantity of liquid to said roller and distributing such liquid in the form of a thin film on the face of the roller, comprising a member in the form of a sheet of rubber-like material having a great number of minute perforations therethrough, and means for supporting said perforated member pressed against the face of said roller with the perforations open to the face of the roller and with the rear ends of said perforations closed.

5. In a moistening mechanism, the combination of a roller, means for rotating said roller, and means for applying a quantity of liquid to said roller and distributing such liquid in the form of a thin film on the face of the roller, comprising a member in the form of a sheet of rubber-like material having a great number of minute perforations therethrough substantially perpendicular to the plane of the sheet, a bar of yielding material to the face of which said perforated member is secured by means of cement so as to close the rear ends of said perforations, and means for supporting said bar with said perforated member pressed against the face of the roller so as to cause said perforations to be open to the roller for distributing the liquid in the form of a film on the face of the roller.

6. In a moistening mechanism, the combination of a roller, means for rotating said roller, and means for applying a quantity of liquid to said roller and distributing such liquid in the form of a thin film on the face of the roller, comprising a member in the form of a sheet of rubber-like material having a great number of minute perforations therethrough substantially perpendicular to the plane of the sheet, a bar of sponge rubber having the pores open at one face, means for securing said perforated member on said face of said. bar with the perforations therethrough in communication with the pores of the bar, and means for supporting said bar with said perforated member pressed against the face of the roller so as to cause said perforations to be open to the roller for distributing the liquid in the form of a film on the face of the roller.

7. In a moistening mechanism, the combination of two rollers in cooperative relation to each other for feeding a sheet forwardly therebetween, means for rotating said rollers, a cushioning member in th form of a bar of yielding material extending along the face of one of said rollers, a member in the form of a sheet on the face of said cushioning member and having perforations therethrough open at the outer face of the sheet for storing liquid on the face of said cushioning member, means for holding said cushioning member and said perforated member in contact with said one roller so as to provide in effect a trough between the perforated memher and the roller adapted to receive a quantity of liquid and to prevent the liquid from escaping downwardly along the face of the roller, and means for delivering liquid to said roller and said perforated member for distribution in the form of a thin film on the face of said roller.

8. In a moistening mechanism, the combination of two rollers in cooperative relation to each other for feeding a sheet forwardly therebetween, means for rotating said rollers, a bar of sponge rubber extending along the rear face of the uppermost one of said rollers, a sheet of rubber-like material on the face of said sponge rubber bar and having perforations therethrough open at the outer face of the sheet for storing liquid on the face of said bar and adapted to prevent the liquid from escaping down the face of the roller, means for holding said sponge rubber bar and said rubber-like sheet in contact with said upper roller so as to provide in effect a trough between the perforated sheet and the roller, and means for delivering liquid to said trough for distribution in the form of a thin film on the face of said roller.

WILLIAM E. DENISON. 

